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proximity of existing ranch roads, TC does not plan or anticipate the need for new road construction to access the
<br /> drill-site. With dry ground conditions, drilling equipment and supplies should be able to travel the short distance
<br /> overland from the existing roads to the drill-site, without significant surface disturbance. Installation of the
<br /> dewatering borehole will involve placement of construction erosion controls (silt fence and/or straw wattles)
<br /> around the downslope margins of the drill pad, removal and windrowing of available soil materials from a
<br /> maximum 100 x 150 foot (0.35 acres) pad area, grading to establish a level drill-pad, excavation of one or more
<br /> temporary cuttings pits on the drill-pad, drilling and casing of the borehole, and installation of a protective access
<br /> manhole. During drilling, a 14-inch diameter steel casing will be placed and grouted in the borehole. On
<br /> completion of drilling and casing operations, the cuttings pits will be allowed to dry-out, material excavated from
<br /> the pits will be replaced and graded, a protective cover consisting of an 10-foot length of 8-foot diameter CMP
<br /> with steel lid and with lightening protection will be installed, a 400hp submersible downhole pump will be
<br /> installed in the well, and the pad surface will be seeded to control erosion and sediment.
<br /> Pipeline installation will involve removal and windrowing of soil materials from the pipeline construction
<br /> corridor (maximum - 50-foot wide) to one side; trenching, with the excavated material to be placed on the
<br /> opposite side; placement of suitable bedding materials; placement, connection, and pressure testing of the
<br /> pipeline; backfilling and compaction of suitable fill materials around and over the pipeline; backfilling and
<br /> compaction of the trench; regrading, replacement of soil materials; and revegetation of all disturbed areas. The
<br /> pipeline will be constructed using high-strength fused HDPE pipe, buried approximately 5-feet deep. A maximum
<br /> of five access/inspection manholes will be located at key points along the pipeline route. A power distribution
<br /> line will be extended approximately 6,800 feet from the 6MN Ventilation Installation, to provide power for the
<br /> 19-Right Dewatering Borehole. Powerline installation will require installation of approximately 25-35
<br /> powerpoles, and a pole-mounted transformer will feed the required pump supply and controls within the borehole
<br /> manhole structure. Powerpoles will include installed raptor protection to minimize the potential for electrocution
<br /> and discourage use as perches.
<br /> During construction, and for the minor surface structures that will remain during mining, drainage and sediment
<br /> control will be provided by Alternative Sediment Controls (ASC's) consisting of combined Best Management
<br /> Practice (BMP) measures. Construction-related surface disturbance will be limited to soil removal and windrowing
<br /> from the pipeline trench alignments and stockpiling for the borehole pad area, excavation of the trenches and
<br /> temporary stockpiling of excavated material adjacent to the trench, minor cut/fill grading to establish the borehole
<br /> drill-pad, and excavation of temporary cuttings pits. The pad for the 19RT Mine Dewatering Borehole installation has
<br /> been designated as a Small Area Exemption (SAE), and the limited drainage from this area will be controlled by
<br /> staked straw wattles, and reclamation/stabilization of the pad area following well installation. Temporary drainage
<br /> and sediment control measures will remain in-place until vegetation is sufficiently established to effectively control
<br /> runoff, erosion,and sediment loss.
<br /> Following installation of appropriate ASC's for each portion of the project disturbance,available soil materials will be
<br /> bladed from any new disturbance areas and temporarily windrowed or stockpiled on the upgradient edge of these
<br /> disturbance areas. For pipeline trench areas, consideration of soil horizon segregation must be balanced with the
<br /> objective of limiting overall surface disturbance. In the interest of minimizing overall surface disturbance, TCC
<br /> proposes to not segregate and separately stockpile individual soil horizons for the pipeline trench disturbance, and
<br /> submits that this approach will not significantly alter soil suitability characteristics, since the differences between the
<br /> soil horizons is not significant over the areas to be affected by trenching. For the borehole drill-pad, individual soil
<br /> horizons will be segregated,if present.
<br /> Soil materials will be replaced following completion of pipeline installation. Reseeding of the disturbed areas
<br /> will be completed during the first appropriate planting period following soil material replacement. When no
<br /> longer needed to support ongoing or future mining and related operations, the dewatering borehole will reclaimed
<br /> by removing the surface manhole structure, plugging and sealing the borehole, consistent with State Engineer
<br /> requirements; cutting-off the casing below ground level, and placing a permanent marker; then regrading,
<br /> replacing soil materials, and reseeding the associated disturbance area. Pipelines will be abandoned in-place, with
<br /> the ends of the pipelines cut-off and capped below grade.
<br /> 5-Main North Borehole and Pipelines and Future Passive Water Treatment System(MR14-283,MR15-288,
<br /> MR16-295, TR16-84) — In conjunction with the planned Wolf Creek Reserve development and mining
<br /> operations, TC anticipates the need to dewater two large bodies of water which have accumulated in the sealed
<br /> TR16-84 2.05-50.10 08/20/18
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